Code identifying the type of communication channel being used.
Code
Description
AA
Circuit switching
A process that, on demand, connects two or more data terminal equipments and permits the exclusive use of a data circuit between them until the connection is released (ISO).
AB
SITA
Communications number assigned by Societe Internationale de Telecommunications Aeronautiques (SITA).
AC
ARINC
Communications number assigned by Aeronautical Radio Inc.
EDI transmission
Number identifying the service and service user.
EM
Electronic mail
Creating/sending/receiving of unstructured free text messages or documents using computer network, a mini- computer or an attached modem and regular telephone line or other electronic transmission media.
